diff --git a/pyproject.toml b/pyproject.toml
index cd4366d01..cefed62ba 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -69,7 +69,7 @@ dev = [
 ]
 
 docs = [
-    "sphinx~=7.4.7",
+    "sphinx>=7.4.7,<9.2.0",
     "furo~=2025.9.25",
     "requests~=2.32.5",
     "pydantic~=2.12.3",